CN104158199B - Power system real-time status is carried out the system and method for reactive power and voltage control - Google Patents

Abstract

The invention discloses a system and method for optimally controlling reactive power and voltage in the real-time state of a power system, using a data acquisition and screening module, a BPA data analysis module, a BPA data flow verification module, a BPA data network equivalent module, and a CIM model The analysis module, parameter setting module, reactive voltage optimization module, result display output module and database module perform real-time data collection, analysis, reactive voltage optimization calculation and result output comparison, and export real-time BPA data and CIM model data respectively, The two types of power flow data are analyzed, and the reactive power optimization calculation based on the interior point method based on complementary constraints is used to obtain the optimal setting of the power grid transformer gear and the optimal switching strategy of the capacitor reactor group, and give the power grid reactive power compensation. Optimizing the configuration side can realize the coordinated control of the reactive power of the whole network, improve the voltage quality of the whole network, improve the voltage security and reduce the effect of active power loss in the operation of the power grid.

Description

System and method for optimal control of reactive voltage and real-time state of power system

technical field

The invention relates to the technical field of power grid reactive power analysis and optimal control, in particular to a system and method for reactive power voltage optimal control aiming at the real-time state of a power system.

Background technique

Formulating a reasonable power system reactive power operation mode is a very important task with high technical content and complex content, which is related to the safe and stable operation of the power grid, and it is also a daily work of power grids at all levels. With the increasing expansion of the power system, the access of new energy sources, the interconnection of AC and DC systems, the coordination of water, fire and power dispatching, the formulation of the operation mode of the power grid has become increasingly complex, and more and more issues need to be considered. At the same time, due to the different work experience and different ways of considering problems of the personnel responsible for formulating the reactive power operation mode of the power grid, and the constraints of the completion time of the specific operation mode, the reactive power operation modes formulated by different personnel have different differences, and sometimes it is difficult to find a satisfactory result after spending a lot of time and effort.

Contents of the invention

The purpose of the present invention is to provide a control system and method for power system real-time reactive voltage optimization based on real-time data of the power grid, and provide an adjustment strategy for real-time voltage control of power system operation.

To achieve the above object, the present invention adopts the following technical solutions:

A system for reactive power and voltage optimal control of the real-time state of a power system, characterized in that it includes a data acquisition and screening module, a BPA data analysis module, a BPA data flow verification module, a BPA data network equivalent module, and a CIM model analysis module , parameter setting module, reactive power and voltage optimization module, result display output module and database module;

The function of the data acquisition and screening module is to use the data acquisition interface to collect the CIM model data and BPA data from the power grid OPEN3000 system and the SCADA system respectively to obtain the network frame data and operation data of the current system operation, and select and enter the data according to the exported data type. The calculation process corresponding to the data type;

The function of the BPA data power flow verification module is to calculate the power flow according to the exported BPA data file, and judge the convergence of the power system power flow described by the data file;

The function of the BPA data analysis module is to analyze the basic parameters of each component of the power system and the corresponding operating parameters according to the card type and data structure in the BPA data file, and convert them into a custom data format, including the overall system parameters, balance Node parameters, transmission line parameters, grounding branch parameters, transformer information, adjustable capacitor reactance parameters, node power parameters, active output parameters, reactive output parameters, voltage parameters, current parameters, renumber nodes, and generate BPA The node number comparison table corresponding to the node name in the data;

The function of the BPA data network equivalent module is based on the power flow calculation results of BPA data, using the equivalent generator principle to convert the entire network data into equivalent generators for systems outside the area that needs to be controlled by reactive power and voltage, and reducing the network required for calculation scale;

The role of the CIM model parsing module is to generate grid data of the power system by analyzing the topological relationship of the power system equipment stored in the CIM model in the XML file in units of classes; The data is combined with the generated grid data to obtain a custom data format, including overall system parameters, balanced node parameters, transmission line parameters, grounding branch parameters, transformer information, adjustable capacitive reactance parameters, node power parameters, and active output parameters, reactive output parameters, voltage parameters, current parameters;

The function of the parameter setting module is to form the constraint conditions of the optimization parameters and determine the control variables participating in the optimization before the reactive power optimization, including setting the control parameters of the system, the constraint parameters and the control strategy parameters of the system, and adding the optimization parameters to the customized Among the data, the calculation data finally used for reactive power optimization calculation is formed;

The role of the reactive voltage optimization module is to adjust the generator output of the power system, the tap position of the on-load tap changer, and the switching of the capacitor reactor group, so that the voltage at each busbar of the system meets the requirements of each voltage level. Security constraints require and optimize the network loss of the system.

The role of the database module is to manage the data required for calculation and store it in the form of a data table; the database used is the ACCESS database;

The function of the result display output module is to display and compare the control variables and state variables after the reactive power optimization calculation. For the calculation results in the BPA data format, the calculation results need to be written back to the BPA data file, and the final result file is output.

A control method adapted to the above-mentioned reactive power and voltage optimization control system for the real-time state of the power system, which performs reactive power optimization calculations for the power system described by the CIM model data file exported by OPEN3000 and the BPA format data file exported by the SCADA system ; Concretely include the following steps:

Step 1, get the data file:

Obtain the real-time BPA data file in DAT format of the power system operation from the SCADA system through the data interface, and obtain the CIM model file from the OPEN3000 system, including the XML format grid data file in the CIM format file and the DT format operation data file;

Step 2, perform power flow calculation or data analysis according to the type of data file:

For BPA data files, follow the steps below to perform power flow calculations:

(1) Use the PSD-BPA power system analysis software to execute the power flow calculation program on the BPA data file, and check whether the operation mode is reasonable; judge the convergence of the power flow calculation through the PFO result file of the power flow calculation, and if the power flow calculation is convergent, proceed to the next step Calculation; if the power flow calculation does not converge, you need to check and modify the BPA data file, and execute the power flow calculation again after the completion, and only when the convergence condition of the power flow calculation is met can you enter the reactive power optimization calculation;

(2) According to the power system grid and operation data information described in each card in the BPA data format, analyze and convert the BPA format into a custom data format, including the active and reactive output of the power plant, and the active and reactive power of the load The output, the bus voltage at the load, the switching status of the capacitive reactor group and the gear position value of the tap of the on-load tap changer, renumber the nodes, and generate a node number comparison table corresponding to the node name in the BPA data;

(3) Using the self-defined equivalent method, by converting the system equivalent outside the required equivalent area into a constant generator output, the BPA format data is equivalent to the relevant area where real-time reactive voltage optimization control area is required; equivalent Targeted reactive power optimization in the value area, while reducing the calculation scale of the system and speeding up the calculation speed to meet the requirements of real-time control optimization;

For CIM data files, follow the steps below for data analysis:

(1) According to the power system equipment stored in the CIM model in the XML file as a unit, analyze its topological relationship, and generate the grid data of the power system; through the corresponding equipment name, combine the operating data in the DT file with the generated grid Data combination, so as to obtain a custom data format, including the active and reactive output of the power plant, the active and reactive output of the load, the bus voltage at the load, the switching status of the capacitor reactor group and the tap of the on-load tap changer gear value;

(2) Select a generator in the system as the balancing machine, and use it as the balancing node of the system in the optimization calculation;

Step 3, set optimization parameters:

Set system control parameters, system constraint parameters, system control strategies and overall system parameters; control parameters include the control variables involved in reactive power optimization, including which transformers and capacitive reactors participate in reactive power optimization adjustment; system constraint parameters include system state variables on The limit value of the lower limit, including the upper and lower limits of the voltage; the system control strategy is the basic parameters of the control variables, including the relevant basic parameters of the transformer and the capacitor reactor; the overall system parameters include the selection of the objective function and the setting of the number of iterations; then, the set The parameters are written into the custom data as the calculation data for reactive power optimization;

Step 4, optimize the calculation:

Power system reactive power optimization is a nonlinear mixed integer programming problem that includes continuous and discrete variables. Therefore, the reactive power optimization calculation is performed using the modern interior point theory based on complementary theory; if the reactive power optimization calculation converges, the calculation result is output; if the calculation does not Convergence, it is necessary to readjust the system control parameters, constraint parameters and control strategy and then perform reactive power optimization calculation again; finally obtain the reactive power and voltage optimization control strategy that meets the safe and stable operation of the power system;

Step 5, generate the result table related to the control variables and state variables, and compare and analyze the bus voltage, generator output, transformer tap position and compensation equipment switching status of the system before and after optimization; so far, the CIM data file described The reactive power optimization calculation of the power system is completed; the reactive power optimization of the power system described in the BPA data file enters step six;

Step 6: Write back the optimized calculation results to the BPA data file, and use the PSD-BPA power system analysis software to verify the power flow; if the power flow calculation converges, output the system power flow results after writing back; if not converge, then It is necessary to adjust the constraint settings and control variable settings in the optimization process, and then perform step 4 again.

This method can achieve the following effects:

(1) Through the data interface, OPEN3000 and SCADA system in the power system can obtain real-time operation mode data of the power system, and analyze the acquired grid data and operation data. Perform reactive power optimization on the power system to be solved, and quickly obtain adjustment strategies for transformer taps, switching of reactive power compensation devices, active and reactive power output of generators, and other control variables that meet the safety and stability requirements of the power system. Optimal control provides theoretical basis and reference.

(2) Compared with the traditional real-time reactive voltage control means AVC, this method adopts the modern interior point algorithm to optimize the whole network, and obtains the optimal control strategy under the operation constraints of the system, which can improve the reactive power of the power system as a whole. power voltage level.

(3) Compared with the traditional reactive power optimization method, this method obtains the real-time data of the power system operation through the design interface, analyzes the custom data format and performs optimization calculations, so that the reactive power optimization method is successfully applied to the power system. in real-time control.

(4) According to the obtained data, the online and offline calculation of the power system can be performed. When the acquired data is real-time data, real-time optimization calculation is online calculation. If the data of the planning and design and the formulated operation mode are imported, it can be verified whether the system planning and design is reasonable or whether the formulated operation mode meets the requirements of the system operation.

Description of drawings

Fig. 1 is a flow chart of the method for reactive voltage optimal control according to the real-time state of the power system according to the present invention.

detailed description

Test case one:

Taking a regional power grid as an example, real-time reactive power and voltage optimization control is carried out on the BPA data under Fengda mode in 2013.

Step 1: Obtain the BPA data under the Fengda method in 2013 through the data interface.

Step 2: The result of power flow verification shows that the real-time BPA data power flow calculation is convergent.

Step 3: From the BPA data of the regional power grid including the regional power grid, find out the system information related to the regional power grid, and make an equivalent value of the power system outside the region. The pre-equivalent system contains 10567 nodes and 7680 transmission lines. After custom equivalence, the equivalence system contains 2175 nodes and 1683 transmission lines. The size of the system to be optimized is greatly reduced.

Step 4: Set system optimization parameters.

(1) Control variable parameter setting

Control variables include: active power output, reactive power output, transformer taps, and the number of capacitive reactor switching groups. in:

Reactive power output: BQ nodes of the power grid, etc.;

Transformer taps: adjustable substation transformer taps for each voltage level of the power grid;

Capacitive reactor capacity: the capacitor configuration capacity and reactor configuration capacity of each substation in the power grid.

(2) Constraint condition parameter setting

Constraint parameters include: tie line reactive power constraint, node voltage;

Node voltage: the voltage limit includes the bus voltage of the power grid 500kV, 220kV, 110kV, 35kV and below 35kV, and the terminal voltage of the generator;

The restricted range is as follows:

Table 1-1 Node voltage limit range

Bus voltage level (kV) Voltage limit range (kV) 500 500-550 220 220-242 110 106.7-117 35 33.95-37.45 10 10-10.7

Remark:

1. The 220kV substation bus of the power grid:

Jiulong, Yanling, Longwan, Ganggang, Gaosha, Yajiang, Bangpu, Lanping.

2. The 110kV substation bus of the power grid:

Longwan, Harbor, Gaosha, Yajiang, Bangpu, Lamping, Niutouwan, Liuwu, Wangxian, Lingshan, Foziao, Jinliang, Square, Guozishan, Xiaodong, Luwu, Baishishui, Zhaixu, Naqian, Real Madrid, Guozishan, Bonded, Datian, Jiangdong, Shitang, Shaping, Yanling.

3. The 35kV substation busbar of the power grid:

Niutouwan, Liuwu, Naqian, Baishishui, Lingshan, Zhaixu, Jinliang, Datian, Real Madrid, Shitang, Shaping, Wangxian, Xiaodong, Luwu.

4. The 10kV substation busbar of the power grid:

Longwan 10KV Ⅱ section, port, Gaosha, Yajiang, Niutouwan, Liuwu, Wangxian, Lingshan, Foziao, Jinliang, Plaza, Guozishan, Free Trade Zone, Real Madrid, Datian, Jiangdong, Bangpu, Lanping, Longwan 10KVI Duan, Xiaodong, Luwu, Baishishui, Zhaiwei, Naqian, Shitang, Shaping.

Step five: use the modern interior point method based on complementary theory for optimization calculation.

Step 6: The voltage over-limit situation and control amount before and after optimization are shown in Table 1-2, Table 1-3, Table 1-4, and Table 1-5. Table 1-6 and Table 1-7 show the control quantity change table.

Step 7: According to the BPA data writing rules, each adjusted control quantity will be written into the BPA data file, and the power flow calculation will be performed. Table 1-2, Table 1-3, Table 1-4, and Table 1-5 show the voltage comparison before and after writing back.

Voltage Quality Analysis:

In the 220kV busbar, the voltage is all qualified, and there is no limit violation before and after optimization.

In the 110kV busbar, before optimization, 7 nodes exceeded the limit, and the proportion of the limit exceeded 21.21%. After optimization, no node exceeded the limit, but due to errors in the write-back, 1 node exceeded the limit and the value was very small after the write-back.

In the 35kV bus, 12 nodes exceeded the limit before optimization, and the proportion of the limit exceeded 63.16%. After optimization, no node exceeded the limit, but due to errors in the write-back, 2 nodes exceeded the limit after the write-back, and the value of the limit was very small .

In the 10kV bus, 22 nodes exceeded the limit before optimization, and the proportion of the limit exceeded 53.66%. After optimization, no node exceeded the limit, but due to errors in the write-back, 3 nodes exceeded the limit after the write-back, and the value of the limit was very small .

Table 1-2 Analysis of 220kV voltage class bus voltage over-limit situation of power grid before and after optimization

Table 1-3 Analysis of 110kV voltage level bus voltage over-limit situation of power grid before and after optimization

Table 1-4 Analysis of 35kV voltage level bus voltage over-limit situation of power grid before and after optimization

Table 1-5 Analysis of 10kV voltage class bus voltage over-limit situation before and after optimization

Table 1-6 Locations of main transformer taps before and after optimization

Table 1-7 Summary table of reactive power compensation capacity of each substation in the power grid before and after optimization Unit: Mvar

Result analysis:

After optimization using this method, the voltage quality of the power grid has been significantly improved; in the 110kV bus, the proportion of out-of-limit before optimization reached 21.21%, and no node out-of-limit after optimization. In the 35kV bus, the proportion of out-of-limit before optimization reached 63.16%, and no node out-of-limit after optimization. In the 10kV bus, the proportion of out-of-limit before optimization reached 53.66%, and no node out-of-limit after optimization.

Due to the reasonable switching of capacitors and reactors and the adjustment of transformer taps, the control of the busbar voltage of each station in the power grid meets the system voltage operation requirements. The reactive power flow on the lines of the entire network is also significantly reduced, and there is no large-capacity reactive power transmission on the lines, so that the network loss of the power grid has been effectively controlled. Before optimization, the active network loss of the power grid was 20.322MW, and after optimization The active network loss is 19.471MW, and the active network loss after optimization is 0.851MW lower than before optimization.

Test case two:

Using the same power system as the test example 1, obtain its CIM data file at 12:03 on March 29, 2013, and optimize the reactive power and voltage control. The basic system data and voltage limit requirements are consistent with the test and are omitted here.

Step 1: Obtain the CIM data file, including grid data in DAT format and operation data in E format.

Step 2: Combining grid data and operating data, analyze and generate custom format data required for optimal calculation.

Step 3: Select the 500kV busbar of Jiulong Substation as the system balance node.

Step 4: Select the adjustable control variables of the system (generator reactive output, on-load tap changer tap, capacitive reactor) and the upper and lower limits of the voltage limit, etc.

Step five: use the modern interior point method based on complementary theory for optimization calculation.

Step 6: The voltage over-limit before and after optimization and the control amount are shown in Table 2-1. Table 2-2 and Table 2-3 show the control quantity change table.

(1) Voltage quality analysis:

Table 2-1 shows the situation of grid bus voltage out of limit before and after optimization. Before optimization, there were 6 nodes in power grid out of limit. Through the calculation of reactive power optimization module, no node out of limit after optimization. The specific results are analyzed as follows:

In the 220kV busbar, the voltage is all qualified, and there is no limit violation before and after optimization.

In the 110kV busbar, one node was out of limit before optimization, but no node was out of limit after optimization.

In the 35kV busbar, there were 5 nodes out of limit before optimization, and no node out of limit after optimization.

In the 10kV busbar, the voltage is all qualified, and there is no limit violation before and after optimization.

Table 2-1 Analysis of grid bus voltage over limit before and after optimization

Table 2-2 Locations of main transformer taps before and after optimization

Table 2-3 Summary table of reactive power compensation switching of each substation in the power grid before and after optimization Unit: Mvar

Result analysis

After adopting software optimization, the voltage quality of the power grid under the cross-section operation mode at 12:03 on March 29, 2013 has been significantly improved; before optimization, 6 nodes of the power grid exceeded the limit. Through the calculation of the reactive power optimization module, the optimized After that, no node exceeded the limit, and the specific results are as follows: In the 110kV bus, there was one node that exceeded the limit before optimization, but no node exceeded the limit after optimization. In the 35kV busbar, there were 5 nodes out of limit before optimization, and no node out of limit after optimization.

Due to the reasonable switching of capacitors and reactors and the adjustment of transformer taps, the control of the bus voltage of each plant and station of the power grid meets the "Power System Voltage Quality and Reactive Power Management Regulations" and "China Southern Power Grid Power System Quality and Reactive Power Management Standards" . The reactive power flow on the lines of the whole network is also significantly reduced. There is no large-capacity reactive power transmission on the lines, so that the network loss of the power grid has been effectively controlled. The total network loss of the power grid before optimization is 13.44MW. The loss is 10.74MW, and the total network loss after optimization is 2.7MW less than that before optimization.

Claims (3)

1. the system that power system real-time status is carried out reactive power and voltage control, it is characterised in that include data acquisition Collection and screening module, BPA data resolution module, BPA data flow correction verification module, BPA data network equivalence module, CIM Parsing module, parameter setting module, reactive Voltage Optimum module, result show output module and DBM；

The effect of data acquisition and screening module is to use data acquisition interface from electrical network OPEN3000 system and SCADA system Upper gather rack data and the service data that CIM data and BPA data acquisition current system run respectively, and according to leading The data type gone out selects to enter the calculation process corresponding with this data type；

The effect of BPA data flow correction verification module is to carry out Load flow calculation according to the BPA data file derived, it is judged that this data literary composition The convergence of the electric power system tide that part describes；

The effect of BPA data resolution module is according to the type of card in BPA data file and data structure, parses electric power The basic parameter of each element of system and the operational factor of correspondence, be converted into self-defining data form, comprise system total Body parameter, balance node parameter, transmission line parameter, ground connection branch parameters, transformator information, tunable capacitor reactance parameter, joint Point power parameter, force parameter of gaining merit, idle go out force parameter, voltage parameter, current parameters, node is renumberd, and Generate the node serial number synopsis corresponding with node name in the middle of BPA data；

The effect of BPA data network equivalence module is the calculation of tidal current according to BPA data, uses equivalence to send out whole network data Principle of Electric Engine, needing the system equivalent carried out beyond reactive power/voltage control region to become electromotor, reduces the network of required calculating Scale；

The effect of CIM parsing module is to set according to the power system stored in units of class in CIM in XML file Standby, by analyzing its topological relation, generate the rack data of power system；By corresponding device name, in the middle of DT file Service data be combined with the rack data of generation, thus obtain self-defining data form, comprise system population parameter, balance Node parameter, transmission line parameter, ground connection branch parameters, transformator information, tunable capacitor reactance parameter, node power parameter, Gain merit force parameter, idle go out force parameter, voltage parameter, current parameters；

The effect of parameter setting module is before carrying out idle work optimization, forms the constraints of parameters optimization and determines that participation is excellent The control variable changed, including the control strategy parameter of control parameter, constrained parameters and the system arranging system, parameters optimization Join in the middle of self-defining data, form the calculating data calculated eventually for idle work optimization；

The effect of reactive Voltage Optimum module be the generator output to power system, on-load transformer tap changer gear, The switching of capacity reactance device group is adjusted, so that the voltage at each bus of system meets the safety of each electric pressure Constraint requirements, and optimize the via net loss of system；

The effect of DBM is the data needed for management calculates, and stores with data tableau format；

Result show output module effect be to idle work optimization calculate after control variable and state variable be shown with And compare, the result of calculation for BPA data form then needs result of calculation to be written back in the middle of BPA data file, exports Whole destination file.

The system that power system real-time status is carried out reactive power and voltage control the most according to claim 1, its feature Being, the data base that described DBM uses is ACCESS data base.

3. one kind with the system phase that power system real-time status is carried out reactive power and voltage control described in claim 1 or 2 The BPA form number that the control method adapted to, the CIM data file derived for OPEN3000 and SCADA system derive Idle work optimization calculating is carried out according to the power system described by file；It is characterized in that, specifically include following steps:

Step one, acquisition data file:

From SCADA system, the DAT form real-time BPA data file of Operation of Electric Systems is obtained by data-interface, from OPEN3000 system obtains CIM file, including the XML format rack data file in CIM formatted file and DT lattice Formula service data file；

Step 2, carries out Load flow calculation or data parsing according to the type of data file:

Load flow calculation follows the steps below for BPA data file:

(1) use PSD-BPA power system analysis software that BPA data file is performed flow calculation program, verify the method for operation The most reasonable；Judge that Load flow calculation restrains situation by Load flow calculation PFO destination file, as Load flow calculation is restrained, then under carrying out The calculating of one step；If Load flow calculation is not restrained, then need check and revise BPA data file, after completing, again perform tide Stream calculation, the condition meeting Load flow calculation convergence could enter idle work optimization calculating；

(2) according to the power system rack described by each card in BPA data form and service data information, by BPA form Resolve and be converted into self-defining data form, comprise power plant meritorious and idle exert oneself, load meritorious and idle exert oneself, negative At load, busbar voltage, the switching situation of capacity reactance device group and the gear value of on-load transformer tap changer, carried out node Renumber, and generate the node serial number synopsis corresponding with node name in the middle of BPA data；

(3) self-defined equivalence method is used, by the system equivalent outside required choropleth is become constant generator output, will BPA formatted data equivalence is the relevant range needing to carry out reactive power voltage optimization control area；Choropleth is had for Property carry out idle work optimization, the calculating scale of reduction system simultaneously, accelerate to calculate speed, to meet wanting of controlling in real time to optimize Ask；

Data parsing follows the steps below for CIM data file:

(1) according to the power system device stored in units of class in CIM in XML file, analyze its topological relation, generate The rack data of power system；By corresponding device title, by the rack data knot of the service data in the middle of DT file with generation Close, thus obtain self-defining data form, comprise power plant meritorious and idle exert oneself, load meritorious and idle exert oneself, negative Busbar voltage, the switching situation of capacity reactance device group and the gear value of on-load transformer tap changer at load；

(2) electromotor in selection system is as balancing machine, as the balance node of system in optimizing calculating；

Step 3, arranges parameters optimization:

The control parameter of system, system restriction parameter, system control strategy and system population parameter are set；Control parameter to include Participate in the controlled quentity controlled variable of idle work optimization, participate in idle work optimization including which transformator and capacity reactance device and adjust；System restriction is joined Number includes the limits value of system state variables bound, including voltage bound；System control strategy is the basic of control variable Parameter, including transformator and the relevant basic parameter of capacity reactance device；System population parameter includes the selection of object function and changes The setting of generation number；Then, in the middle of the parameter read-in self-defining data that will set, as the calculating number of reactive Voltage Optimum According to；

Step 4, optimizes and calculates:

Reactive power optimization of power system is one and comprises continuously and discrete variable Nonlinear Mixed Integer Programming Problem, therefore uses Modern interior-point theory based on complementary theory carries out idle work optimization calculating；If idle work optimization calculates convergence, then output calculates knot Really；Do not restrain if calculated, then again perform nothing after needing to readjust system control parameters, constrained parameters and control strategy Merit optimization calculates；Finally obtain and meet the reactive power and voltage control strategy that power system safety and stability runs；

Step 5, generates the result form that control variable and state variable are relevant, to the busbar voltage of the system before and after optimizing, The switching situation of generator output, load tap changer gear and the equipment of compensation is analyzed；So far, CIM data file The idle work optimization of described power system calculates and terminates；The idle work optimization of the power system described by BPA data file enters Step 6；

Step 6, is written back in the middle of BPA data file optimizing the result after calculating, and uses PSD-BPA Power System Analysis Software carries out trend checking to it；System load flow result as Load flow calculation is restrained, after output write-back；If do not restrained, need to adjust Constraint setting and control variable in the middle of whole optimization process are arranged, and the most again perform step 4.